Although the present invention is applicable for the deep fat frying of numerous food products, it has been found to be particularly useful in the frying of frozen french fry cut potato pieces or breaded type snack foods in a bar or fast food environment. Therefore, as not to limit the application of this invention to particular food products, the invention will be described in this environment.
Deep fat fryers are widely used in the restaurant business for cooking various food products, such as french fried potatoes, chicken, and fish. Typically, such french fryers comprise a deep tank containing a pool of cooking oil in the lower part of the tank with the cooking oil being heated by an immersed electric heating element or by a gas flame. The uncooked product is placed in a basket which is lowered into the heated oil for the desired cooking period. When the product is done, as determined by visual inspection by the restaurant employee, or by the sound of an audio timer, the basket should be removed from the oil by the employee, drained, and the product served to the customer.
With the advent of convenience stores, and the present market trends towards self serve fast food sales in these locations, the need to provide those food products mentioned above has increased. The equipment to fill this need must be safely and easily operated by the customer, reliable, easy to clean and service and not pollute the surrounding environment.
In the Prior Art, various machines are known for processing and dispensing small batches of a food product such as french fried potatoes.
U.S. Pat. No. 3,818,820 discloses an automatic machine for preparing fried potato product which includes a food hopper, a slideable ejection scoop for dispensing product into a cooking basket, a means to immerse the product in cooking oil for a predetermined time, and a means to pivot the basket and drop the potato product into a waiting container. The machine also contains a fan to extract the fumes via a replaceable charcoal filtering unit. An automatic fire extinguisher unit is mounted near the frying container to extinguish the oil if it should catch fire.
U.S. Pat. No. 3,981,232 discloses a free standing deep fat fryer with a fry container located in the interior of a cabinet. The cabinet includes an upper portion which houses a fan means for extracting air and fumes from the cabinet and forcing same through filter means which includes charcoal. A fire extinguisher is also disclosed.
U.S. Pat. No. 4,489,647 discloses an enclosed free standing deep fat fryer with a fan, filter and electrostatic precipitator means for extracting air and fumes from the cooking area. Disclosed is manually operated means for placing food products into oil, cooking those food products and delivering them back to the operator. Complex chutes and mechanical systems caused severe problems with cleaning, jamming and reliability. Filter systems were unsealed and blow by of unfiltered air occurred.
U.S. Pat. No. 4,505,194 discloses an enclosed free standing deep fat fryer with a fan, filter and electrostatic precipitator means for extracting air and fumes from the cooking area. Disclosed is motor driven means for placing food products into oil, cooking those food products and delivering them back to the operator. Complex chutes and mechanical systems caused severe problems with cleaning, jamming and reliability. Filter systems were unsealed and blow by of unfiltered air occurred.
U S. Pat. No. 4,520,717 discloses an enclosed free standing deep fat fryer with a fan and filter means for extracting air and fumes from the cooking area. Disclosed is an integral means for heating the cooking oil. A fire extinguisher is also disclosed.
U.S. Pat. No. 4,539,898 discloses an enclosed free standing deep fat fryer with a fan and filter means for extracting air and fumes from the cooking area. Disclosed is an integral means for heating the cooking oil. A means for automatically lowering a cooking basket containing food into a vat containing cooking oil for a predetermined time and then raising the cooking basket out of the oil is disclosed. A fire extinguisher is also disclosed.
U.S. Pat. No. 4,722,267 discloses an enclosed free standing coin operated french fry vending machine. Disclosed is a storage compartment for foodstuffs. A means for metering foodstuffs, immersing said foodstuffs in hot oil and dispensing said foodstuffs is also disclosed. An oil circulating, filtering, heating and replenishment system is disclosed.
U.S. Pat. No. 4,785,725 discloses an automatic cooking machine using a supply of hot cooking oil to cook food stuffs such as french fries. Disclosed is a mechanical means for collecting foodstuffs from an opened top cartridge cooking the foodstuffs and returning the foodstuffs to the opened top cartridge. A fire extinguisher is disclosed. An oil circulating, filtering, heating and replenishment system is disclosed.
U.S. Pat. No. 4,852,471 discloses a semiautomatic food frying apparatus. A particular basket design is disclosed. Air filter means is disclosed. A plate like heating means is disclosed.
U.S. Pat. No. 4,854,949 discloses a ventless exhaust system for a food cooking apparatus. Disclosed is a grease filter, an electrostatic precipitator, a flame arrestor and a fire extinguisher. A fan is also disclosed.
U.S. Pat. No. 4,898,091 and Canadian Pat. No. 1,257,103 disclose an enclosed free standing deep fat fryer with a fan and filter means for extracting air and fumes from the cooking area. A means for sealing the enclosure to ensure that all fumes pass through the filter before being allowed to exit the cooking area is also disclosed. Disclosed is an integral means for heating the cooking oil. A means for automatically lowering a cooking basket containing food into a vat containing cooking oil for a predetermined time and then raising the cooking basket out of the oil is disclosed. A fire extinguisher is also disclosed.
U.S. Pat No. 4,902,316 discloses a ventless exhaust system for a conventional oven. A fan to direct air flow is disclosed. Also disclosed are an aluminum filter, electrostatic precipitator and a charcoal filter.
The present invention as claimed is intended to solve various prior art deficiencies, related reliability problems of complex mechanisms, food storage and spoilage problems. Almost all machines have problems with pollution of the surrounding environment. In the scope of the disclosure of almost all patents in this art unit, air filters are disclosed. In most cases, the filters as disclosed fail to address the problems of physical and chemical processes that must occur to properly clean emitted fumes. The major source of pollution from this class of machines is leakage of unfiltered air around and through the filter systems and also from the cooking area. In addition, the food handling systems of many inventions as disclosed are very complex and jamming due to oil degradation and food product build up through use occurs. Food basket design as disclosed in the Prior Art fails to take into account product flow dynamics and oil surface tension problems, allowing food products to become trapped and leading to incomplete unloading of the food products. In addition, many machines do not allow simple disassembly for cleaning and easy replacement of parts.